summaryrefslogtreecommitdiffstats
path: root/drivers/block
diff options
context:
space:
mode:
authorIlya Dryomov <idryomov@gmail.com>2020-02-12 15:23:58 +0100
committerIlya Dryomov <idryomov@gmail.com>2020-03-30 12:42:40 +0200
commit59e542c869895fb37005b60058a342187bb63c61 (patch)
treecbc74c491fbd4c77894a79b358d8ebac84aa4f27 /drivers/block
parenta52cc685753568e5bcbe762586c2bfbe7175255e (diff)
downloadlinux-59e542c869895fb37005b60058a342187bb63c61.tar.gz
linux-59e542c869895fb37005b60058a342187bb63c61.tar.bz2
linux-59e542c869895fb37005b60058a342187bb63c61.zip
rbd: embed image request in blk-mq pdu
Avoid making allocations for !IMG_REQ_CHILD image requests. Only IMG_REQ_CHILD image requests need to be freed now. Move the initial request checks to rbd_queue_rq(). Unfortunately we can't fill the image request and kick the state machine directly from rbd_queue_rq() because ->queue_rq() isn't allowed to block. Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Diffstat (limited to 'drivers/block')
-rw-r--r--drivers/block/rbd.c138
1 files changed, 51 insertions, 87 deletions
diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
index acda61f5be03..3af09a0f208b 100644
--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -337,10 +337,7 @@ struct rbd_img_request {
u64 snap_id; /* for reads */
struct ceph_snap_context *snapc; /* for writes */
};
- union {
- struct request *rq; /* block request */
- struct rbd_obj_request *obj_request; /* obj req initiator */
- };
+ struct rbd_obj_request *obj_request; /* obj req initiator */
struct list_head lock_item;
struct list_head object_extents; /* obj_req.ex structs */
@@ -1610,20 +1607,11 @@ static bool rbd_dev_parent_get(struct rbd_device *rbd_dev)
return counter > 0;
}
-/*
- * Caller is responsible for filling in the list of object requests
- * that comprises the image request, and the Linux request pointer
- * (if there is one).
- */
-static struct rbd_img_request *rbd_img_request_create(
- struct rbd_device *rbd_dev,
- enum obj_operation_type op_type)
+static void rbd_img_request_init(struct rbd_img_request *img_request,
+ struct rbd_device *rbd_dev,
+ enum obj_operation_type op_type)
{
- struct rbd_img_request *img_request;
-
- img_request = kmem_cache_zalloc(rbd_img_request_cache, GFP_NOIO);
- if (!img_request)
- return NULL;
+ memset(img_request, 0, sizeof(*img_request));
img_request->rbd_dev = rbd_dev;
img_request->op_type = op_type;
@@ -1631,8 +1619,6 @@ static struct rbd_img_request *rbd_img_request_create(
INIT_LIST_HEAD(&img_request->lock_item);
INIT_LIST_HEAD(&img_request->object_extents);
mutex_init(&img_request->state_mutex);
-
- return img_request;
}
static void rbd_img_capture_header(struct rbd_img_request *img_req)
@@ -1667,7 +1653,8 @@ static void rbd_img_request_destroy(struct rbd_img_request *img_request)
if (rbd_img_is_write(img_request))
ceph_put_snap_context(img_request->snapc);
- kmem_cache_free(rbd_img_request_cache, img_request);
+ if (test_bit(IMG_REQ_CHILD, &img_request->flags))
+ kmem_cache_free(rbd_img_request_cache, img_request);
}
#define BITS_PER_OBJ 2
@@ -2834,10 +2821,11 @@ static int rbd_obj_read_from_parent(struct rbd_obj_request *obj_req)
struct rbd_img_request *child_img_req;
int ret;
- child_img_req = rbd_img_request_create(parent, OBJ_OP_READ);
+ child_img_req = kmem_cache_alloc(rbd_img_request_cache, GFP_NOIO);
if (!child_img_req)
return -ENOMEM;
+ rbd_img_request_init(child_img_req, parent, OBJ_OP_READ);
__set_bit(IMG_REQ_CHILD, &child_img_req->flags);
child_img_req->obj_request = obj_req;
@@ -3638,7 +3626,7 @@ again:
goto again;
}
} else {
- struct request *rq = img_req->rq;
+ struct request *rq = blk_mq_rq_from_pdu(img_req);
rbd_img_request_destroy(img_req);
blk_mq_end_request(rq, errno_to_blk_status(result));
@@ -4692,68 +4680,25 @@ static int rbd_obj_method_sync(struct rbd_device *rbd_dev,
static void rbd_queue_workfn(struct work_struct *work)
{
- struct request *rq = blk_mq_rq_from_pdu(work);
- struct rbd_device *rbd_dev = rq->q->queuedata;
- struct rbd_img_request *img_request;
+ struct rbd_img_request *img_request =
+ container_of(work, struct rbd_img_request, work);
+ struct rbd_device *rbd_dev = img_request->rbd_dev;
+ enum obj_operation_type op_type = img_request->op_type;
+ struct request *rq = blk_mq_rq_from_pdu(img_request);
u64 offset = (u64)blk_rq_pos(rq) << SECTOR_SHIFT;
u64 length = blk_rq_bytes(rq);
- enum obj_operation_type op_type;
u64 mapping_size;
int result;
- switch (req_op(rq)) {
- case REQ_OP_DISCARD:
- op_type = OBJ_OP_DISCARD;
- break;
- case REQ_OP_WRITE_ZEROES:
- op_type = OBJ_OP_ZEROOUT;
- break;
- case REQ_OP_WRITE:
- op_type = OBJ_OP_WRITE;
- break;
- case REQ_OP_READ:
- op_type = OBJ_OP_READ;
- break;
- default:
- dout("%s: non-fs request type %d\n", __func__, req_op(rq));
- result = -EIO;
- goto err;
- }
-
/* Ignore/skip any zero-length requests */
-
if (!length) {
dout("%s: zero-length request\n", __func__);
result = 0;
- goto err_rq;
- }
-
- if (op_type != OBJ_OP_READ) {
- if (rbd_is_ro(rbd_dev)) {
- rbd_warn(rbd_dev, "%s on read-only mapping",
- obj_op_name(op_type));
- result = -EIO;
- goto err;
- }
- rbd_assert(!rbd_is_snap(rbd_dev));
- }
-
- if (offset && length > U64_MAX - offset + 1) {
- rbd_warn(rbd_dev, "bad request range (%llu~%llu)", offset,
- length);
- result = -EINVAL;
- goto err_rq; /* Shouldn't happen */
+ goto err_img_request;
}
blk_mq_start_request(rq);
- img_request = rbd_img_request_create(rbd_dev, op_type);
- if (!img_request) {
- result = -ENOMEM;
- goto err_rq;
- }
- img_request->rq = rq;
-
down_read(&rbd_dev->header_rwsem);
mapping_size = rbd_dev->mapping.size;
rbd_img_capture_header(img_request);
@@ -4782,21 +4727,50 @@ static void rbd_queue_workfn(struct work_struct *work)
err_img_request:
rbd_img_request_destroy(img_request);
-err_rq:
if (result)
rbd_warn(rbd_dev, "%s %llx at %llx result %d",
obj_op_name(op_type), length, offset, result);
-err:
blk_mq_end_request(rq, errno_to_blk_status(result));
}
static blk_status_t rbd_queue_rq(struct blk_mq_hw_ctx *hctx,
const struct blk_mq_queue_data *bd)
{
- struct request *rq = bd->rq;
- struct work_struct *work = blk_mq_rq_to_pdu(rq);
+ struct rbd_device *rbd_dev = hctx->queue->queuedata;
+ struct rbd_img_request *img_req = blk_mq_rq_to_pdu(bd->rq);
+ enum obj_operation_type op_type;
- queue_work(rbd_wq, work);
+ switch (req_op(bd->rq)) {
+ case REQ_OP_DISCARD:
+ op_type = OBJ_OP_DISCARD;
+ break;
+ case REQ_OP_WRITE_ZEROES:
+ op_type = OBJ_OP_ZEROOUT;
+ break;
+ case REQ_OP_WRITE:
+ op_type = OBJ_OP_WRITE;
+ break;
+ case REQ_OP_READ:
+ op_type = OBJ_OP_READ;
+ break;
+ default:
+ rbd_warn(rbd_dev, "unknown req_op %d", req_op(bd->rq));
+ return BLK_STS_IOERR;
+ }
+
+ rbd_img_request_init(img_req, rbd_dev, op_type);
+
+ if (rbd_img_is_write(img_req)) {
+ if (rbd_is_ro(rbd_dev)) {
+ rbd_warn(rbd_dev, "%s on read-only mapping",
+ obj_op_name(img_req->op_type));
+ return BLK_STS_IOERR;
+ }
+ rbd_assert(!rbd_is_snap(rbd_dev));
+ }
+
+ INIT_WORK(&img_req->work, rbd_queue_workfn);
+ queue_work(rbd_wq, &img_req->work);
return BLK_STS_OK;
}
@@ -4963,18 +4937,8 @@ out:
return ret;
}
-static int rbd_init_request(struct blk_mq_tag_set *set, struct request *rq,
- unsigned int hctx_idx, unsigned int numa_node)
-{
- struct work_struct *work = blk_mq_rq_to_pdu(rq);
-
- INIT_WORK(work, rbd_queue_workfn);
- return 0;
-}
-
static const struct blk_mq_ops rbd_mq_ops = {
.queue_rq = rbd_queue_rq,
- .init_request = rbd_init_request,
};
static int rbd_init_disk(struct rbd_device *rbd_dev)
@@ -5007,7 +4971,7 @@ static int rbd_init_disk(struct rbd_device *rbd_dev)
rbd_dev->tag_set.numa_node = NUMA_NO_NODE;
rbd_dev->tag_set.flags = BLK_MQ_F_SHOULD_MERGE;
rbd_dev->tag_set.nr_hw_queues = 1;
- rbd_dev->tag_set.cmd_size = sizeof(struct work_struct);
+ rbd_dev->tag_set.cmd_size = sizeof(struct rbd_img_request);
err = blk_mq_alloc_tag_set(&rbd_dev->tag_set);
if (err)